Derby Talk

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Vitamin K wrote:
So here's the problem I want to solve: There's no good way for cubs to true up their wheels that can be done without expensive equipment. There exists the Derbyworx wheel shaver, but I've actually become less pleased with this tool, the more I've worked with it and evaluated the output.

Anyhow, as before, just thinking out loud here. The ultimate goal would be to put more accessible tools into the hands of Scouts that could effectively yield quality parts without the need to resort to expensive equipment, or external services. All thoughts welcome.

I guess my question would be why do you feel that is a problem worth solving? I know many folks go to incredible lengths to attempt to get what they feel are superior wheels (measuring, sorting, etc). I can tell you from my experience, we've never done that. We do a quality bore prep, but I've never touched any other part of the wheel. We've won every race we've ever been in at Pack/District level. For Mid-America, I purchase wheels, but I've never "tested" the run-out on any purchased wheel and we've been top 5 in MidAmerica graphite division last two years running.

Vitamin K wrote:
So here's the problem I want to solve: There's no good way for cubs to true up their wheels that can be done without expensive equipment. There exists the Derbyworx wheel shaver, but I've actually become less pleased with this tool, the more I've worked with it and evaluated the output.

Anyhow, as before, just thinking out loud here. The ultimate goal would be to put more accessible tools into the hands of Scouts that could effectively yield quality parts without the need to resort to expensive equipment, or external services. All thoughts welcome.

I guess my question would be why do you feel that is a problem worth solving? I know many folks go to incredible lengths to attempt to get what they feel are superior wheels (measuring, sorting, etc). I can tell you from my experience, we've never done that. We do a quality bore prep, but I've never touched any other part of the wheel. We've won every race we've ever been in at Pack/District level. For Mid-America, I purchase wheels, but I've never "tested" the run-out on any purchased wheel and we've been top 5 in MidAmerica graphite division last two years running.

Well, I guess one has to make up one's own mind about what is worth doing. There are a lot of components to a well running car build and wheel quality is just one of them.

Personally, I've always found it fun to find ways that we're able to improve the running of our cars. The kids like being able to measure wheels on the gauge to find the roundest ones. I think they would also enjoy using a mini-lathe that actually worked to remove small amounts of material from the outer tread. IIRC, I think Stan Pope mentioned helping his son and grandson work wheels on his lathe.

As far as measuring wheels from vendors, well, I think there's two reasons to do that. One, is to get an idea of what constitutes a 'professionally done wheel'. Two is to see how well a given vendor's claims actually stack up against their product, and those of others vendors. Consumers ought to be informed.

I have one last set of wheels coming. As soon as they arrive I'll list the results. Since this Topic is leaning toward turning wheels on a lathe I'd like to post it under this topic. We'll see what happens.

I'm still waiting on the last set of wheels but it won't make much difference with the quality because of the price. I have Knotty Racing gauge and the drop indicator from Derby Evolution. I have 3 scales, one of which goes to .01 grams, and 3 weights, 100 grams, 200 grams, and 5 ounces. All scales weigh correctly. No work was done on the wheels except to make them round.

Well, I with our Pack Derby Season creeping closer, my thoughts have returned to all of the PWD craziness that tends to rattle around in my head. I found my little wheel-turning-mount setup and decided to go ahead and test the runout on it (which I'd planned to do a long, long time ago). After rigging together a horrible assortment of clamps and shims, I was able to get my dial indicator up against the pin while I turned the shaft.

Radial runout reads right at about .001", which I think should be sufficient for my purposes. Would be nice if I could start out more accurate than that, but one can only do so much with this kind of setup. I suspect that the pin gage may not be perfectly round or straight, as I get better readings if I just measure the shaft itself. Also, the further away from the base of the mounted pin that I measure, the more runout I get. Still, this shouldn't be a problem, given that the bore of the wheel is going to sit at the base of the pen.

So now I just need to figure out the drive mechanism and the tool mount. No sweat there, right?